Recent years have seen an increased interest in advanced user interfaces, particularly those used in connection with personal computers, tablet computers, smart-phone devices, and other electronic systems. Input devices often used in connection with such systems include proximity sensor devices (also commonly called touchpads or touch sensor devices). A proximity sensor device typically includes a sensing region, often demarked by a surface, in which the proximity sensor device determines the presence, location and/or motion of one or more input objects. Proximity sensor devices may be used to provide interfaces for the electronic system. For example, proximity sensor devices are often used as input devices for larger computing systems (such as opaque touchpads integrated in, or peripheral to, notebook or desktop computers).
It is sometimes desirable to provide a “virtual” user interface experience through the use of interface components that mimic the operation of physical user interface devices such as touchpads, keyboards, and the like. Such virtual user interfaces might observe the gestures and/or the postures made by a user's body (e.g., the user's hand) in a two-dimensional or three-dimensional space.
Presently known virtual user interfaces are unsatisfactory in a number of respects. For example, user interfaces that make use of three-dimensional space are seen as fatiguing and ergonomically inefficient. Furthermore, real-time interpretation of gestures and postures in three dimensions is computationally difficult and can lead to misinterpreting a user's actions—i.e., reading unintentional gestures as intentional gestures. This is often referred to as the “live-mic” problem.
Accordingly, there is a need for improved virtual user interfaces that address these and other limitations of the prior art.